Combine the flour, baking powder and salt in a small bowl and mix together thoroughly with a whisk or fork. Set aside.

Place the butter and chocolate in a medium heatproof bowl in a wide skillet of barely simmering water and stir occasionally until melted and smooth. Remove from the heat and set aside.

In a large bowl, using an electric mixer, beat the eggs, sugar, coffee beans, and vanilla until pale and thick, about 5 minutes. Stir in the chocolate mixture. Stir in the flour mixture and, finally, the nibs. Cover the dough and refrigerate until firm, about 1 hour, or up to 4 days.

Position the racks in the upper and lower thirds of the oven and preheat the oven to 350 degrees. Line two cookie sheets with parchment or wax paper.

Drop rounded teaspoonfuls of batter 1 1/2 inches apart on the lined cookie sheets. Bake, rotating the sheets from top to bottom and front to back halfway through the baking time to ensure even baking, until the cookies are puffed and dry on the surface but still soft and gooey within, 7 to 9 minutes. Carefully slide the cookies, still on the parchment, onto racks. Let cool completely. (The cookies can be stored, airtight, at room temperature for 2 days, or frozen for longer storage.)

Recipe Copyright© Alice Medrich: Bittersweet; Recipes and Tales from a Life in Chocolate